The present invention relates generally to apparatus for diagnostic testing of a patient's pulmonary system, and more particularly, is directed to a disposable radioactive aerosol inhalation apparatus.
In order to perform ventilation scanning studies on a patient, it is necessary for the patient to inhale radioactive materials. In this manner, diagnostic testing and treatment of, for example, the lungs of the patient, can be performed.
However, the handling of radioactive materials can be dangerous. Therefore, an apparatus is known from U.S. Pat. No. 4,510,929, the entire disclosure of which is incorporated herein by reference, which provides for such diagnostic testing using radioactive materials. Such apparatus is portable, adequately shields the hospital staff from radioactive exposure, and is disposable. Generally, the radioactive material is mixed with incoming oxygen in a nebulizer so as to become aerosolized with the aid of an orifice-diffuser arrangement. Then, the patient breathes through a first tube which is connected with the nebulizer so that minute particles of the radioactive material are supplied to the patient's lungs.
The arrangement of this apparatus, however, is somewhat complex. In the first place, it requires separate conduits for inhale and exhale, with a valve situated in each conduit, and with a third conduit interconnecting the inhale and exhale conduits. The valves are necessary to prevent any exhale through the inhale conduit, and to prevent any inhale through the exhale conduit. Further, the exhale conduit is connected to a filter, the latter positioned in a common housing adjacent the nebulizer. The outlet of the filter is in the closed housing and, in this regard, the housing has an approximate volume of three liters. Because of this arrangement of the filter and nebulizer, the apparatus becomes relatively bulky.
Still further, the parts of the nebulizer are separately constructed, thereby rendering the structure complex and the assembly thereof time-consuming, thus increasing the cost of the apparatus. In addition, because of the arrangement in this apparatus, if there is a short interruption in the supply of oxygen or radioactive material, or if supplies of the same are sporadic, there may not be an even distribution of the radioactive material with the oxygen. Also, the arrangement of the diffuser may not satisfactorily break up the radioactive particles.